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// RUN: %check_clang_tidy -std=c++11-or-later %s performance-no-automatic-move %t
struct Obj {
Obj();
Obj(const Obj &);
Obj(Obj &&);
virtual ~Obj();
};
struct NonTemplate {
NonTemplate(const Obj &);
NonTemplate(Obj &&);
};
template <typename T> struct TemplateCtorPair {
TemplateCtorPair(const T &);
TemplateCtorPair(T &&value);
};
template <typename T> struct UrefCtor {
template <class U = T> UrefCtor(U &&value);
};
template <typename T>
T Make();
NonTemplate PositiveNonTemplate() {
const Obj obj = Make<Obj>();
return obj; // selects `NonTemplate(const Obj&)`
// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: constness of 'obj' prevents
// automatic move [performance-no-automatic-move]
}
TemplateCtorPair<Obj> PositiveTemplateCtorPair() {
const Obj obj = Make<Obj>();
return obj; // selects `TemplateCtorPair(const T&)`
// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: constness of 'obj' prevents
// automatic move [performance-no-automatic-move]
}
UrefCtor<Obj> PositiveUrefCtor() {
const Obj obj = Make<Obj>();
return obj; // selects `UrefCtor(const T&&)`
// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: constness of 'obj' prevents
// automatic move [performance-no-automatic-move]
}
Obj PositiveCantNrvo(bool b) {
const Obj obj1;
const Obj obj2;
if (b) {
return obj1;
// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: constness of 'obj1' prevents automatic move [performance-no-automatic-move]
}
return obj2;
// CHECK-MESSAGES: :[[@LINE-1]]:10: warning: constness of 'obj2' prevents automatic move [performance-no-automatic-move]
}
// FIXME: Ideally we would warn here too.
NonTemplate PositiveNonTemplateLifetimeExtension() {
const Obj &obj = Make<Obj>();
return obj;
}
// FIXME: Ideally we would warn here too.
UrefCtor<Obj> PositiveUrefCtorLifetimeExtension() {
const Obj &obj = Make<Obj>();
return obj;
}
// Negatives.
UrefCtor<Obj> Temporary() { return Make<Obj>(); }
UrefCtor<Obj> ConstTemporary() { return Make<const Obj>(); }
UrefCtor<Obj> ConvertingMoveConstructor() {
Obj obj = Make<Obj>();
return obj;
}
Obj ConstNrvo() {
const Obj obj = Make<Obj>();
return obj;
}
Obj NotNrvo(bool b) {
Obj obj1;
Obj obj2;
if (b) {
return obj1;
}
return obj2;
}
UrefCtor<Obj> Ref() {
Obj &obj = Make<Obj &>();
return obj;
}
UrefCtor<Obj> ConstRef() {
const Obj &obj = Make<Obj &>();
return obj;
}
const Obj global;
UrefCtor<Obj> Global() { return global; }
struct FromConstRefOnly {
FromConstRefOnly(const Obj &);
};
FromConstRefOnly FromConstRefOnly() {
const Obj obj = Make<Obj>();
return obj;
}
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